The present invention relates to a technique for repairing with laser a convex portion of pattern shapes on a substrate on which a predetermined pattern is formed, and which repairs a defective portion by coating wiring material thereon. This technique is suitable for use in a method for manufacturing a display apparatus. In addition, the present invention relates to a method for manufacturing the display apparatus, and in particular, it relates to a technique which prevents a failure in the circuit pattern from occurring in the case where the circuit pattern has already been built on a TFT (thin-film transistor) substrate and the like.
A liquid crystal display has a structure in which liquid crystal is interposed between two glass substrates. On one of the glass substrates, also referred to as “color filter (CF) substrate”, there is formed a color filter on which blue, green and red resin (color resin) are alternately coated. On the other glass substrate, also referred to as “active matrix substrate” or “thin film transistor (TFT) substrate”, pixel circuit constructed of thin film transistor, wiring, a drive circuit, and the like are formed.
A pattern defect in the color filter and/or wiring may cause a display abnormality, resulting in that the liquid crystal display becomes a defective product. This display abnormality includes, for example in the case of the color filter substrate, a color defect (mixed color) caused by the color resin, being coated on the color filter, which runs over the adjacent pixel, or an uneven coating caused by non-uniformity in the resin film thickness. As for the active matrix substrate, the display abnormality may include short-circuit in wiring and a break in wiring.
The color filter and wiring of the liquid crystal display are formed by superimposing several layers of patterns on one another. Therefore, it is necessary to repair the pattern defect before an upper layer pattern is formed. As a method for detecting a pattern defect, it is possible to use a general pattern inspection apparatus utilizing image processing.
As a method for repairing such run-over of color resin on the color filter or short-circuit in wiring, Japanese Patent Laid-open Publication No. H09-307217 discloses a general method, where the short-circuited portion is irradiated with laser beam to remove this portion. If a pattern of the same shape is formed in repeated manner as in the case of liquid crystal display, the Japanese Patent Laid-open Publication No. H05-27111 discloses a repairing technique where the laser beam is irradiated via a mask having a standard pattern shape, and a part different from the standard pattern is removed and the repair is performed. As a method for coating wiring material onto the pattern defective part, there is a method as disclosed by Japanese Patent Laid-open Publication No. H08-66652 where coating is performed by use of a hollow pipette with a narrow tip diameter.
In addition, Japanese Patent Laid-open Publication No. H10-177844 discloses a technique to repair a short-circuit defect occurred in a circuit pattern in a semiconductor device, by opening the defect with laser processing. In addition, Japanese Patent Laid-open Publication No. H10-324973 discloses a technique to repair an open-circuit defect occurred in a circuit pattern in a semiconductor device, by changing a metallic material such as palladium (material of the circuit pattern) into liquid state or gaseous state, and by coating or spraying thus converted metallic material onto the open-circuit defective part.